Police and fire alarm system.



G. L. HUGHES.

POLICE AND FIRE ALARM SYSTEM. APPLICATION TILED FEB. 12, I1913. 1 105,43 Patented July 28, 1914 2 SHEETS-SHEET 1.

51" umdoz G eor geL,Hughes G. L. HUGHES.

POLICE AND FIRE ALARM SYSTEM.

APPLICATION FILED IBB.12,1913.

1,105,436, Patented July 28,1914,

2 SHEETSBHEET 2.

Li anue mtoz' l q vihwoow G801" g L Q5 156a. I a-mzgg UNITED STATESPATENT OFFICE.

GEORGE L. HUGHES, OF CHICAGO, ILLINOIS, ASSIGNOR OF ONE-HALF TO ROBERTE. COOPER, OF HOPKINSVILLE, KENTUCKY.

POLICE AND FIRE ALARM SYSTEM.

Specification of Letters Patent.

Patented July 28, 1914.

Application filed February 12, 1913. Serial No. 747,974.

To all whom it may concern:

Be it known that I, GEORGE L. I-IUGHEs, a citizen of the United States,residing at Chicago, in the county of Cook and State of Illinois, haveinvented certain new and useful Improvements in Police and FireAlarmSystems; and I do declare the following to be a full, clear, andexact description of the invention, such as will enable others skilledin the art to which it appertains to make and use the same.

This invention relates to improvements in telephone systems and moreparticularly a police and fire alarm system combined with the ordinarycommon battery telephone system.

The principal object of this invention is to provide a direct fire orpolice alarm in connection with a telephone system which may be operatedby any subscriber without the intervention of a central operator andwhich at the same time will give an alarm to such operator or othertelephone employee to allow his supervision and assistance if necessary.

Further objects of the invent-ion are to provide a system of thischaracter which will enable the subscriber to obtain a direct connectionwith the fire or police station quickly so as to make every telephone afire alarm box and to do this at the least possible cost; to indicatewhich subscribers line is calling the special station, that is, the fireor police station, and to lock such connection and thereby enable a callto be traced to its source; to enable the telephone operator to listenand supervise the call to the special station and at the same time notallow such operator to cut off the connection with the special station;to give a distinctive signal, (such for instance, as a red lamp) of callto the special station; and to sound a bell or other audible or visualsignal at the telephone central station when the special station iscalled.

The above and other objects are attained in the embodiment of theinvention herein shown and described and by the slight addition of thefollowing parts to the ordinary common battery telephone system, namely:a switch at the subscribers station to ground the line, a signalingdevice at the fire station and at the central station, the addition of adifierential and oppositely wound relay in connection with the doublewound line relay and audible and visible signals for the telephoneoperator.

The invention further consists in the various novel features ofconstruction and arrangement hereinafter described and claimed, andillustrated in the accompanying drawings, in which- Figure 1 is adiagrammatic view of my police and fire alarm system shown in connectionwith a portion of an ordinary common battery telephone system, the partsbeing in their normal position; and Fig. 2 is a similar view showing theposit-ion of the parts when the subscriber calls the special stationsuch as a fire station or police station.

Referring more particularly to the drawings S represents a subscribersstation, C the central station and F the fire or other special stationof which there may be any number. 1 and 2 represent the branches of thetelephone line connecting the subscriber with central and at thesubscribers station S I have illustrated the ordinary telephone setconsisting of the transmitter 3, receiver 4, telephone switch hook 5,polarized call bell 6 and a condenser 7. In addition to these usualparts, the only change which my system entails is the provisions of asuitable switch 9 which may be of any construction such as an ordinaryone or two spring push button, a glass covered circuit closure such ascommonly used in fire alarm systems, etc; and the terminals of thisswitch are connected to ground at 10 and to the branch 1 of thetelephone line as shown.

11 and 12 represent the branches of the line extending from central tothe special station F which latter preferably contains a transmitter 13and receiver 14 connected in series with the branch 11; a telephoneswitch hook 15 connected to the branch 12 and adapted when elevated toclose the talking circuit through the receiver 14 and transmitter 13 andwhen depressed by the weight of the receiver to connect onto thebranches 11 and 12 by means of conductors 16, 17, the coil of a relay orelectromagnetic circuit closure 18. The latter is adapted to close asuitable alarm circuit 19 for the fire station which circuit as hereshown embodies trated the subscribers line 23, the subscribers line lamporother signal 24 and an ordinary line relay 25 which latter is of thedouble coil type including coils O and N. The terminals of the line jack23 are connected to the telephone line branches 1, 2 and this line jackcontrols through contact springs 26 of the circuit 27 of the line lamp24. One branch of the circuit 27 is connected to a battery 28 whichlatter is grounded at 29 and the other branch of said circuit 27 isconnected to ground at 30 through spring contacts 31 controlled by thearmature of the line relay 25.

In order to advise the central operator or wire chief or other employeethat the fire or other special station has been called I provide avisual signal 32 in the form of an ordinary tell tale lamp and anaudible signal 33 such as an electric gong. The latter is included inthe circuit 34 containing a battery 35 or other electrical generator andspring contacts 36 controlled by the armature of a relay orelectromagnetic circuit closure 37. The armature of this relay 37 alsocontrols the circuit closing contacts 38 of the circuit 39 of the lamp32. This cir cuit has one of its branches grounded at 40 through thecontacts 38 and its other branch connected to a battery 41 which latteris grounded at 42. I also provide at the central station a differentialfire signal and talking relay 43 which has oppositely wound coils F, Eand an armature controlling a plurality of pairs of contact springs 44,45, 46, 47, 48, 49. The contacts 48 and 49 are included in the circuit50 of the coil of the lamp and bell relay 37 and one branch of thiscircuit 50 is grounded at 51 through the contacts 48, 49, and the otherbranch is con nected to a battery 52 which latter is grounded at 53. Thecontacts 46, 47 are connected respectively to the telephone line branchwire 2 and the fire station branch wire 12 while the contacts 44 and 45are connected respectively to the telephone line branch wire 1 and thefire station branch wire 11 so that the relay 43 when actuated isadapted to close the telephone line 1, 2 of the subscriber onto the line11, 12 of the fire or other special station and also to close thecircuit through the relay 37 which in turn gives the central operatorthe audible and visual signals to advise that the special station hasbeen called so that such central ofiice employee may plug in at the linejack 23 and listen to the conversation and supervise.

The coils N, O of the line relay 25 and the coils E, F of the specialstation relay 43 are connected in parallel and the coils E, F are alsopermanently connected on the main telephone line. This is effected byconnecting one terminal of the coil 0 to the branch 2 of the telephoneline at 54 and the other terminal of said coil is connected to a battery55 which latter is grounded at 56. From point 54 the branch 2 extends toand is connected to one terminal of the coil E of the special relay 43and the other terminal of said coil is connected to a battery 57 whichlatter'is grounded at 58. The coils N and F of the relays 24, 43 areconnected together by a conductor 59 and the other terminals of saidcoils N, F are grounded at 60 and 61 respectively. The conductor 59 isconnected between the two relays by a conductor 62 which is connected at63 to the branch 1 of the main line or telephone circuit so that bymeans of the switch key or button 9 at the subscribers station thewinding F of the special magnet 43 may be shunted through the ground andthe coil N ofthe line relay 25 may be energized in shunt with the activecoil of winding E of the special relay 43.

In order to lock the special station relay 43 after it has been actuatedin order that malicious fire calls may be traced and punished, anysuitable mechanical or electrical locking means may be provided. Asillustrated, I have shown a spring catch or look 64 arranged to engageand hold the arma-- ture 65 of the relay 43 when the same has beenactuated. This lock must of course be manually released.

In operation it will be seen that with the parts in normal positionshown in Fig. 1 of the drawings, should a subscriber wish to talk tocentral or to another subscriber, the telephone system is used in theordinary manner and since the coils of the special relay 43 areoppositely wound they will neutralize each other and the special stationwill not be connected to the subscriber. Should the subscriber desire tocall the fire or police or other special station he successively orsimultaneously removes the receiver 4 from the switch hook 5 and closesthe switch 9 which latter shunts the coil winding F of the special relay43 to ground and permits the coil E to attract the armature 65. Thiscircuit will be as follows: from the battery 57 through coil E, branch 2of main line through transmitter 3, receiver 4, switch hook 5, branch 1,switch 9 to ground and to the negative pole of the battery 57. When thespecial relay is energized the contacts 44, 45, 46, 47 will connect themain line branches 1, 2 to the fire station branches 11, 12 and thecontacts 48, 49 will complete the circuit through the lamp and bellrelay 37. The armature of this relay will cause the contacts 36, 38 toclose the circuits 34, 39 and thereby sound the bell 33 and illuminatethe lamp 32 to advise the central ofiice that a special station has beencalled. The lock 64 holds the circuits until relay 43 is manuallyreleased. When the branches 11, 12 and 1, 2 are connected the relay 18will be energized to at tract its armature and thereby cause thecontacts 22 to close the circuit 19 of the fire gong 20 and thus advisethe fire station that a subscriber is calling. When the attendant at thefire station removes the receiver 1 from the switch hook 15 the relay 18is cut out thereby stopping the fire gong and the talking circuitthrough the transmitter 13 and receiver 14 is established. The centraloilice, if desired, can plug in at the line ack 23 and listen to theconversation and see that the alarm is properly turned in therebyovercoming the possible failure of the fire chief to receive the alarmshould the calling subscriber be confused or unable to properlycommunicate the alarm.

From the foregoing it will be noted that by the very simple meansdescribed and shown the ordinary telephone system may be converted intoa very effective fire and police alarm system at extremely small expensesince no complicated special apparatus is necessary and the standardtelephone equipment can be used and easily connected up. Among thefurther advantages of my system it will be noted that the telephoneoperator or other employee cannot cut oft the connection between thesubscriber and the special station but such operator can listen to andsupervise the conversation. A distinctive signal such as a red lamp isgiven to the special station employee and the latter is advised as towhich subscriber is send ing in the alarm. Visible and audible sig nalsare given to the telephone central office when the special station iscalled so that the chief operator or wire chief can have propersupervision,

It will be understood that while I have shown and specifically describedone embodiment of my invention that various modifications may be madeWithout departing from the essential features of my invention,

lVhat I claim is:

l. In a telephone system, the combination with a central station, and aplurality of subscribers stations between which communication may beestablished through the central station; of a differential relay havingtwo coils, one being permanently included in the main line, a switch atthe subscribers station to shunt the other coil through the groundwithout interrupting the subscriber's circuit, a special station, andmeans operated by said relay for establishing telephonic communicationbetween the subscribers station. and the special station.

2. In a telephone system, the combination with a central station, and aplurality of subscribers stations between which lcommunication may beestablished through the central station, the central station including adouble-wound line relay; ot a special station, a differential relay forthe special station and provided with oppositely wound coils, wiringconnecting the two relays in parallel and permanently connecting thespecial station relay on the main line, a switch at the subscribersstation for shunting one of the coils of the special station relaythrough the ground without interrupting the subscribers circuit, andmeans operated by said special station relay for establishing telephoniccommunication between the subscribcrs station and the special station.

3. In a telephone system, the combination with a central station, and aplurality of subscribers stations between which commu nication may beestablished through the central station; of a differential relay havingtwo coils, one being permanently included in the main line, a switch atthe subscribers station to shunt the other coil through the groundwithout interrupting the subscribers circuit, a special station, meansoperated by said relay for establishing telephonic communication betweenthe subscribers station and the special station, and means forpermanently locking said relay atter it has been actuated, whereby itwill be retained in actuated position until released manually by anauthorized person.

41--. In a telephone system, the combination with a central station, anda plurality of subscribers stations betw en which communication may beestablished through the central station; of a differential relay havingtwo coils, one being permanently included in the main line, a switch atthe subscribers station to shunt the other coil through the groundwithout interrupting the subscribers circuit, a special station, analarm mechanism at the special station, a movable member operated bysaid relay for controlling the alarm mechanism and placing the specialstation. in telephonic communication with said subscribers station whensaid relay is actuated, and means whereby said removable member can beactuated after communication has been established between centralstation and sul'iscribers station.

5. In a telephone system, the combination with a central station and aplurality of subscribers stations between which communication may beestablished through the central station, the central station including adouble wound line relay; of a special station, a differential relay forthe special station liming oppositely wound coils, a conductor toconnect one of the ends of a coil from each relay, means to connect saidconductor to the main line, conductors to ground the opposite ends ofthe last mentioned coils, batteries for the main line and said relays,said batteries having one of their poles grounded, conductors connectingone of the ends of the other coils of said relays to the remaining polesof said batteries, other conductors connecting the opposite ends of thelast mentioned coils to the main line, whereby the two relays areconnected in parallel and the special station relay permanentlyconnected to the main line, and means operated by said special stationrelay for establishing communication between the subscribers station andthe special station.

In testimony whereof I have hereilnto set my hand in presence of tWosubscribing Witnesses.

GEORGE L. HUGHES. WVitnesses OTTO N ELSON, PAUL H. ALTEMUER.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents.

Washington, D. G.

